Very nice! I currently use Inkscape (slow) and Krita (a bit difficult to get started with) to edit SVGs. Your tool seems very promising, but it is currently missing a few bits that would be important for me (color fill, gradients, text, layers would be nice).

I am missing the mechanics of making animations. I clicked + a few times and accidentally made a shape move, but I could not replicate it. Any way to delete frames?

Is this a side project? What are your plans for future development?